Expandable shield instrument for use in intraocular surgery

ABSTRACT

An instrument capable of providing large-area shielding within an isolated operating region, such as the eye, while being passable through a small incision in the region through which the instrument must be inserted. For example, an instrument capable of being passed through a typical 3 mm (or smaller) phacoemulsification incision without undue damage to ocular tissue, and which expands to provide large-area shielding, e.g. to occlude a large-diameter (e.g. approx. 6 mm) posterior capsule opening. The surgical instrument includes two or more leaves, the leaves being interconnected by at least one fastener in a manner that causes expansion of a leading or distal portion of the instrument when the following or proximal portions of each leaf are manipulated, whether by a user or through interaction with a wall of the incision.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.12/681,654, filed on May 17, 2010, which claims the priority ofPCT/US2008/078753, filed on Oct. 3, 2008, which is based on and claimspriority to U.S. Provisional Application No. 60/977,867, filed Oct. 5,2007, the entire contents of which are hereby incorporated fully hereinby reference.

FIELD OF THE INVENTION

The present invention relates generally to instruments for use inintraocular surgery, and more particularly to an instrument capable ofproviding large-area shielding within the eye, yet being passablethrough a small incision into the eye.

DISCUSSION OF RELATED ART

Various surgical procedures involve placement of instruments through anincision made in ocular tissue. Exemplary surgical procedures include aphacoemulsification procedure in which a small incision is made in thecornea by a keratome or similar flat-bladed knife. The incision isnecessary to permit insertion of instruments into the eye, and toprovide access to inner portions of the eye during the surgicalprocedure. Because the incision damages ocular tissue, it is desirablethat the damage be limited, and thus that the incision not exceed about3 mm in length. In this exemplary procedure, a phacoemulsification probeis then inserted through the incision and is operated to createhigh-frequency sound waves that break up and/or emulsify the nucleus ofthe eye's lens, which is relatively hard tissue, then aspirate thatemulsified tissue through the small incision. An irrigation/aspirationinstrument may then be inserted through the incision to aspirate thecortex of the lens via suction. A foldable intraocular lens (IOL) maythen be inserted through the incision, using an appropriate cartridgeand injector, and into the capsular bag of the eye.

The wall of the lens capsule is extremely delicate, and posteriorcapsular rupture is not uncommon. Such rupture carries with it the riskof posterior segment complications and continuing inflammation ifcortical and nuclear material released during phacoemulsification of thelens descends to the posterior compartment. Retention of lens materialposteriorly also may necessitate subsequent posterior compartmentsurgery, with its attendant inconvenience and risk.

A number of instruments and techniques have been devised to minimizeloss of lens material into the posterior compartment during cataractsurgery that has been complicated by a tear of the posterior capsule.These include placement of a lens glide through the phacoemulsificationincision, placement of viscoelastic material, either through theoriginal incision or through a pars plana (posterior) incision, andplacement of instruments, some of which have expanding basket-likeprotuberances, through a pars plana incision.

Insertion of a widely-used Sheets lens glide behind the lens materialearly after posterior capsular rupture has been detected is a rapid andsimple method for attempting to limit loss of lens material into theposterior compartment. Such a Sheets lens glide is a disposable, thin(e.g., 6 mil), small (e.g., 2.8 mm by 30 mm) sterile sheet ofpolyethylene, such as that manufactured and/or sold by Texas Technologyof Austin, Tex., USA under the trademark Cleanfilm, or other plasticmaterial that is generally rectangular in shape, and has a width of nomore than the 3 mm (or smaller) incision, to permit it to be insertedthrough the 3 mm (or smaller) incision made in the ocular tissue.Accordingly, the portion of the lens guide positioned intraocularlycannot effectively prevent lens material from descending to theposterior compartment; phacoemulsified lens material may easily passbeside and behind the 3 mm (or smaller) wide lens guide. Viscoelasticmaterial does not present a solid barrier to posterior migration of lensmaterial, and any technique requiring creating and placing instrumentsthrough a pars plana incision entails additional risk of vitreousdisruption, retinal tear, choroidal hemorrhage, and vitreous hemorrhage.Furthermore, such techniques do not provide a barrier to preventsubstantial loss of lens material backward into the posteriorcompartment, especially if the pupil is larger than 3 mm in diameter.

SUMMARY

The present invention provides an instrument capable of providinglarge-area shielding within the eye, while being passable through asmall incision through which the instrument must be inserted into theeye. More specifically, the present invention provides an instrumentcapable of being passed through a typical 3 mm (or smaller)phacoemulsification incision without undue damage to ocular tissue, andwhich expands to provide large-area shielding, e.g. to occlude alarge-diameter (e.g. approx. 6 mm) posterior capsule opening.

In one embodiment, the instrument is specially configured to expandautomatically, through the action of insertion through the incision, andto collapse automatically, through the action of withdrawal through theincision. In one embodiment, the surgical instrument includes two ormore leaves, the leaves being interconnected by at least one fastener ina manner that causes expansion of a (leading/distal) portion of theinstrument when the (following/proximal) portions of each leaf aremanipulated by a user.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of an expandable shield instrument in accordancewith an exemplary embodiment of the present invention.

FIG. 2 is an exploded view of the leaves of the instrument of FIG. 1;FIG. 2 a is an exploded view of another embodiment of the instrument;

FIG. 2 b is an exploded view of yet another embodiment of theinstrument.

FIG. 3 is a plan view of the instrument of FIG. 1, showing theinstrument in a collapsed state suitable for insertion into an incisionin the eye.

FIGS. 4 and 5 are plan views of the instrument of FIG. 1, showing theinstrument in various expanded states as it is inserted through theincision in the eye.

FIG. 6 is a plan view of the instrument of FIG. 1, showing theinstrument in a fully expanded state in the eye; FIG. 6 a is a plan viewof the instrument of FIG. 2 a in s fully expanded state; FIG. 6 b is aplan view of the instrument of FIG. 2 b in s fully expanded state

FIG. 7 is an exploded view of leaves of an expandable shield instrumentin accordance with an alternative embodiment of the present invention;

FIG. 8 is a plan view the instrument including the leaves of FIG. 7,shown in a collapsed state;

FIG. 9 is a plan view the instrument of FIG. 8, showing the instrumentin a fully expanded state in the eye;

FIG. 10 is a plan view of an alternative embodiment of the instrument ofFIG. 8;

FIGS. 11 and 12 are plan views of another alternative embodiment of theinstrument;

FIGS. 13 and 14 are plan views of yet another alternative embodiment ofthe instrument;

FIG. 15 is a plan view of an alternative embodiment of the instrument ofFIGS. 11 and 12; and

FIG. 16 is a plan view of an alternative embodiment of the instrument ofFIGS. 13 and 14.

DETAILED DESCRIPTION

The present invention provides an instrument capable of providinglarge-area shielding within the eye, e.g. a shielding surface having anapproximate maximum length and maximum width each greater than 3 mm,and/or providing a shielding area greater than approximately 9 mm² andpreferably greater than approximately 5 mm in diameter and/or greaterthan approximately 19 mm². The instrument is specially-configured toprovide such large-area shielding and yet to be passable through a smallslit-like incision, e.g. 3 mm or less in width, through which theinstrument must be inserted into the eye during ocular surgery.

FIGS. 1-6 show an exemplary expandable shield instrument 10. As shown inFIGS. 1 and 2, this exemplary instrument includes three leaves 20, 30,40 fixedly joined to one another, but in a manner permitting relativerotational movement of the leaves. In this embodiment, each of theleaves defines an opening 22, 32, 42 toward its respective distal end toallow for insertion of a fastener 50 capable of pivotably joining theleaves, such as a rivet, a plug, post, screw, nut and bolt, etc. Atleast two of the leaves, namely the outer leaves, have curvilinearouter, edges 26 a, 26 b, 46 a, 46 b, as will be further discussed below.

Each leaf 20, 30, 40 is preferably constructed of a thin, e.g. 6 mil inthickness, flat sheet material that is sterilizable and/or otherwisesuitable for insertion in the eye during ocular surgery. Any suitableconventional material may be used, such as polyethylene, such as thatmanufactured and/or sold by Texas Technology of Austin, Tex., USA underthe trademark Cleanfilm. The material should be relatively flexible tolimit the likelihood of damage to ocular tissue, but should be rigidenough to permit the leaves to be somewhat self-supporting when graspedmanually by their proximal ends 24, 34, 44 to permit the leaves to bemanually manipulated during a procedure, and to act as a shield toprevent posterior migration of nuclear fragments, etc. In certainembodiments, the proximal end 24, 44 of each outer leaf 20, 40 includesa substantially straight-edged portion alignable with a substantiallystraight-edged portion of the central leaf 30 with the shield is fullyexpanded, such as the substantially straight-edged and aligned proximalregion 24, 34, 44 of each leaf.

FIGS. 2-6 show the instrument 10 in various states assumed duringinsertion of the instrument into the eye, which is showndiagrammatically as eye tissue 200 having an exemplaryphacoemulsification (or other) incision 210, the eye and incision beingshown in cross-section for illustrative purposes. The exemplary incisionhas a width W_(i), as shown in FIGS. 3-6, of approximately 3 mm or less,as is typical of an exemplary incision made by a keratome in aphacoemulsification procedure. As best shown in FIG. 3, which shows theinstrument in a collapsed state, the leading end 12 of the instrument 10is configurable to a collapsed state in which the leading end has awidth approximately equal to, and preferably less than, the width W_(i)of the incision through which it is intended to be passed, so that theinstrument may be passed into the eye with little or no damage to theocular tissue surrounding the incision.

As the instrument 10 is advanced further into the eye, as shown in FIG.4, the outer leaves 20, 40 may be manually grasped and pivoted about thefastener 50 to expand the leaves to define a shielding portion 14 withinthe eye, e.g., within the anterior chamber of the eye. Additionally, theleaves may be manipulated to maintain an outer boundary B defined by theoverlapping leaves, adjacent the incision in the eye tissue, at a widthapproximately equal to, and preferably less than, the width W_(i) of theincision. This minimizes damage to the ocular tissue surrounding theincision resulting from passing of the instrument therethrough.

It should be noted that in this embodiment, the outer boundary B is a“sliding boundary”, in that is a narrow portion that moveslongitudinally relative to the longitudinal axis of the central leaf 30from a point near the fastener 50, toward a point far from the fastener50 as the outer leaves 20, 40 are pivoted relative to one another duringinsertion of the instrument into the eye. This sliding boundary permitsmaintenance of a minimum width of the instrument adjacent the incision210 that approximates the incision width, and thus minimizes damage toeye tissue during insertion of the device through the incision. See FIG.5 showing further insertion of the instrument 10 into the eye.

When the instrument is fully inserted into the eye, as shown in FIG. 6,the shield portion 12 is fully expanded to provide a maximum area of theshielding surface. It will be noted that the leaves 20, 30, 40 mayoverlap to provide a continuous (or substantially continuous) shieldingsurface area. Accordingly, it will be noted that the maximum width W_(s)of the shield portion 12 within the eye can be manipulated to far exceedthe width W_(i) of the incision through which the instrument must bepassed, as shown in FIG. 6. For example, the shielding portion 12 mayhave an approximate maximum length and maximum width each greater than 3mm, and/or providing a shielding area greater than approximately 9 mm²′and preferably greater than approximately 5 mm in diameter and/orgreater than approximately 19 mm², and thus be suitable for occludingthe posterior capsular opening, for example, which is typically about 6mm in diameter.

It should be noted that it is possible to advance the instrumentdirectly into the eye by manually grasping the central leaf 30 alone,and pushing the instrument through the incision and into the anteriorcompartment of the eye. In this insertion method, the eye tissueadjacent the incision defines a “bottleneck”, and acts as a follower ina cam/follower arrangement, and causes the curvilinear (cam) surfaces ofthe outer leaves 20, 40 to pivot to expand the shield portion 12 as itis advanced into the eye. Similarly, the central leaf 30 alone may begrasped as the instrument is withdrawn from the eye, and the leaves willmove automatically as the curvilinear surfaces 26 a, 46 a ride over theeye tissue adjacent the incision, to automatically move the leaves, suchas into the collapsed state and in any case having the minimum width ofthe tool adjacent the incision to permit removal from the eye.

FIGS. 7-9 show an expandable shield instrument in accordance with analternative embodiment of the present invention. The individual leaves20, 30, 40 define openings 22, 32, 42 at which they may beinterconnected or joined by a fastener 50, etc, as best shown in FIGS. 7and 8. It should be noted that fewer or more than three leaves may beemployed, as desired. In this embodiment, the leaves are generallyrectangular in overall shape, and may be aligned to substantiallyoverlap to define a collapsed state having a width less than a widthW_(i) of the incision in the eye through which it must be passed, asbest shown in FIG. 8. In this embodiment, however, the outer edges ofthe leaves define reentrant shoulders 28, 38, 48 at which the width ofeach leaf is narrowed, as best shown in FIG. 7. The shoulders arepositioned adjacent the fastener 50, as best shown in FIGS. 8 and 9.This permits the instrument 10 to be inserted into the eye to a point atwhich the shoulders 28, 38, 48 span the incision in the eye tissue, asshown in FIG. 9. The provides clearance to limit damage to ocular tissuewhen the distal ends of the leaves are spread apart in fan-like fashionto provide an expanded shield portion 12 within the eye 200, as bestshown in FIG. 9. The distal ends of the leaves may be spread in thismanner by manually manipulating the proximal ends 24, 34, 44 of theleaves 20, 30, 40, which remain outside of the eye and accessible to theeye surgeon. The leaves may be collapsed and withdrawn as desired, in asimilar manner.

FIG. 10 is a plan view of an alternative embodiment of the instrument ofFIG. 8. In this embodiment, the leaves 20, 30, 40 need not include anopening for accommodating a fastener 50. Instead, an elastomeric orother constrictive band 52, may be placed around the leaves in lieu ofanother fastener such as a rivet to provide scissor-like pivoting actionof the leaves. This device may be used, inter alia, in an eye surgery byinsertion through incision in a manner similar to that described abovewith reference to the embodiment of FIGS. 7-9.

FIGS. 11 and 12 are plan views of another alternative embodiment of theinstrument. In this embodiment, a pair of leaves 20, 30 support arelatively smooth continuous membrane 60, such as a thin sheet ofpolyethylene, providing a shielding area approximately 7 mm in diameter.The membrane 60 is sufficiently thin and flexible to be gathered betweenthe leaves 20, 30, or wrapped around one or both of the leaves, toprovide a collapsed state in which an outer width of the instrument isapproximately equal to or less than a width W_(i) of the incisionthrough which it is intended to be passed, e.g. 3 mm or less. Afterinsertion into the eye, the leaves may be separated to extend themembrane 60 therebetween to provide a shield portion 12 within the eye.For illustrative purposes, the instrument is shown in a partiallycollapsed state in FIG. 11, and in a partially expanded state in FIG.12.

FIGS. 13 and 14 are plan views of yet another alternative embodiment ofthe instrument 10. This embodiment is similar in structure and in use tothat shown in FIGS. 11 and 12. However, in this embodiment, the membrane60 includes accordion-style pleats 62 to facilitate collapsing of theinstrument. For illustrative purposes, the instrument is shown in acollapsed state in FIG. 13, and in a partially expanded state in FIG.14.

FIG. 15 is a plan view of an alternative embodiment of the instrument ofFIGS. 11 and 12. This embodiment is similar in structure and use to thatshown in FIGS. 11 and 12, but further includes a fastener 50 joining theleaves 20, 30 so that they may pivot relative to one another. A rivet,as shown in FIG. 15, or similar fastener may be used for this purpose.Optionally, the leaves 20, 30 may include shoulders 28, 38 similar tothose shown in FIGS. 7-10. The instrument may be positioned in collapsedand expanded states by manually manipulating the proximal ends 24, 34 ofthe leaves 20, 30 in a manner similar to that described above.

FIG. 16 is a plan view of an alternative embodiment of the instrument ofFIGS. 13 and 14. This embodiment is similar in structure and use to thatshown in FIGS. 13 and 14, but further includes a fastener joining theleaves 20, 30 so that they may pivot relative to one another. An elasticor inelastic constrictive band 52, as shown in FIG. 16, or similarfastener 50 such as a rivet, may be used for this purpose. Optionally,the leaves 20, 30 may include shoulders 28, 38 similar to those shown inFIGS. 7-10. The instrument may be positioned in collapsed and expandedstates by manually manipulating the proximal ends 24, 34 of the leaves20, 30 in a manner similar to that described above.

Although use of the instrument is described above for illustrativepurposes with respect to use in a phacoemulsification procedure, it issuitable for a variety of uses. Additional exemplary uses of theinstrument include, but are not limited to any invasive surgicalprocedure requiring a shielding or partitioning device through anincision smaller than a desired shield or partition distal end.

In posterior capsular rupture with remaining nuclear fragments, theinstrument may be placed behind the fragments to prevent their posteriordislocation during the attempts at their removal;

When inserting an IOL into the ciliary sulcus in the presence of acapsular rupture, the instrument may be used to guide the lens safelyover the capsular opening and into the sulcus; and

If an IOL is determined to have inadequate capsular support (due, forexample, to the size of a capsular tear or zonular dehiscence), theinstrument may be used to guide the IOL out of the eye, providing abarrier to the posterior compartment.

While there have been described herein the principles of the invention,it is to be understood by those skilled in the art that this descriptionis made only by way of example and not as a limitation to the scope ofthe invention.

1. A surgical instrument comprising a plurality of leaves, the leavesbeing interconnected by at least one fastener in a manner that causesexpansion of a distal portion of the instrument when the proximalportion of at least one leaf is manipulated by a user.
 2. The surgicalinstrument of claim 1, wherein the instrument has a minimum width thatcorresponds to a width of a widest leaf.
 3. The surgical instrument ofclaim 2, wherein the minimum width of the instrument is less than thewidth of a surgical incision in a subject's eye.
 4. The surgicalinstrument of claim 3, wherein the minimum width of the instrument isless than 3 mm, and wherein the width of the surgical incision is lessthan 3 mm.
 5. The surgical instrument of claim 1, wherein the leavesoverlap to form a substantially continuous shielding surface, theshielding surface being located in a region between the distal portionof the instrument and the proximal portion of the instrument.
 6. Thesurgical shielding instrument of claim 5, wherein the surface area ofthe substantially continuous shielding surface is at least double thesurface area of any one leaf in the region.
 7. The surgical instrumentof claim 6, wherein the instrument comprises three leaves, including acentral leaf disposed along a central longitudinal axis of theinstrument, and at least two outer leaves pivotably interconnected tothe central leaf.
 8. The surgical instrument of claim 7, wherein eachleaf is substantially flat.
 9. The surgical instrument of claim 8,wherein each leaf includes a rounded distal end.
 10. The surgicalinstrument of claim 9, wherein all leaves are pivotably interconnectedadjacent the distal end of the instrument, and wherein the outer leaveseach comprise a curvilinear outer portion, and wherein the leaves arearranged such that the minimum width of the instrument can beselectively moved along the longitudinal axis of the instrument betweenthe distal end of the instrument and the proximate end of the instrumentby manipulating the relative positions of the proximate ends of theouter leaves relative to the central leaf.
 11. The surgical instrumentof claim 10, wherein the curvilinear portions interact with the wall ofan incision to automatically adjust the relative position of the outerleaves so that the shielding area increases as the instrument isinserted through the incision to a preselected maximum depth.
 12. Thesurgical instrument of claim 10, wherein the wherein the curvilinearportions interact with the wall of an incision to automatically adjustthe relative position of the outer leaves so that the shielding areadecreases as the instrument is withdrawn from the incision.
 13. Thesurgical instrument of claim 9, wherein the central leaf issubstantially rectangular, and wherein the outer leaves comprise agenerally S-curved shape.
 14. The surgical instrument of claim 9,wherein the minimum width of the instrument is located at an overlappingportion of all leaves.
 15. The surgical instrument of claim 14 whereinthe central leaf is longer than the outer leaves.
 16. The surgicalinstrument of claim 1, wherein all leaves are pivotably interconnectedadjacent the distal end of the instrument, and wherein the outer leaveseach comprise a curvilinear outer portion, and wherein the leaves arearranged such that the minimum width of the instrument can beselectively moved along the longitudinal axis of the instrument betweenthe distal end of the instrument and the proximate end of the instrumentby manipulating the relative positions of the proximate ends of theouter leaves relative to the central leaf.
 17. The surgical instrumentof claim 16, wherein the curvilinear portions interact with the wall ofan incision to automatically adjust the relative position of the outerleaves so that the shielding area increases as the instrument isinserted through the incision to a preselected maximum depth.
 18. Thesurgical instrument of claim 16, wherein the wherein the curvilinearportions interact with the wall of an incision to automatically adjustthe relative position of the outer leaves so that the shielding areadecreases as the instrument is withdrawn from the incision.